Technical Field
The present disclosure relates generally to an anvil assembly which is suitable for use with a circular anastomosis stapler. More specifically, the present disclosure relates to an anvil assembly having a tiltable head with a sliding sleeve.
Background of Related Art
Circular anastomosis staplers which include an anvil assembly having a tiltable anvil head are known in the art. One such circular anastomosis stapler is disclosed in commonly owned U.S. Patent Application Publication No. 2008/0230581 (“'581 Publication”) which is incorporated herein by reference in its entirety. The anvil assembly includes an anvil head pivotally secured on a distal end of a connection post of the anvil assembly. The anvil assembly is provided to a clinician in an operable position, i.e., with the anvil head perpendicular to the connection post.
During an anastomosis procedure, a purse string suture may be used to attach first and/or second sections of the tissue being joined together about the connection post of the anvil assembly. Following the firing operation of the circular anastomosis stapler and as the anvil head is separated from the cartridge assembly of the circular stapler, the anvil head pivots about the distal end of the connection post, to reduce the profile of the anvil head. The anvil assembly may be spring loaded to automatically tilt the anvil head to a maximum angle allowed by the circular stapler and/or anvil head geometry. Tilting the anvil head to reduce the profile of the anvil head within a vessel minimizes contact between the anvil head and the inner walls of the vessel to facilitate removal of the anvil head through an anastomosis ring, i.e., the annular stapled section of tissue, formed by the stapler.
In certain instances, an anastomosis donut, i.e., the tissue severed by an annular knife of the stapling assembly during an anastomosis procedure and the purse string suture(s), if used to secure the tissue section(s) about the anvil assembly, and/or other tissue or obstruction may become pinched by the anvil head as the anvil head is pivoted. When this occurs, the anvil head is inhibited from fully tilting. As a result, the anvil head may contact the interior of the vessel to a greater extent than necessary during withdrawal of the anvil head through the anastomosis ring. Contact of the interior of the vessel may cause unwanted tissue damage (i.e., damage to the anastomosis ring) and/or may result in higher retraction forces being necessary during removal of the anvil head through the vessel.
Therefore, it would be beneficial to have an anvil assembly including a sleeve configured to reposition the anastomosis donut to prevent pinching of the anastomosis donut by the tiltable anvil head, and, thus, allow complete tilting of the anvil head.